Smokeless furnace



3 Sheets-Sheet 1.

{No Model.)

B. A. THOMAS. SMOKBLESS PURNAGE.

Patented July Y9 Hv-r\ llalllilTLl I I l llll L l ...IIIIIFIIIIH l l l l lllll i u O Ou V v 00000 3 Sheets-Sheet 2.

Y(No Model.)

B. A. THOMAS. sMoKBLEss PURNAGB.

Patented July 9 .'Z'OQIZfweo/z.. it may concern p y lBjjjt. "lmovv'n that I, BENJAMIN ARTHUR Savglorias, of Chicago, Illinois, have invented certain new andvr usef,u l; ,l mprovements in 4{Srnoke'less Furnaces; ofl which thefollowiug )sa specification.

al'fntended'tolconsnme the smoke produced by the combustionff- .solid fuel, and to this no only is the smoke lvmainly consumed,l but creased..

.l5 11n Carrying-.eut lmyinvention Iemployhollow grate-bars of a novel ccns'truction, through whichair isadmitted to apoint over or near i thefbridge-walland there mingled with the smoke and unconsnrued carbon, thus-furnishzo 'ing-tothese-.gasesand solids the necessary o irygento support furthercombustion. The

i s rnolre gasee, and heatedair beingthusmixed thefglleat eiiciencyof the fuel isv sensiblyin-y NJAMIN ARrnURnr-IOMAS, oroincAeo, ILLiNoIs, Assienon .Torri-'Illi- ENGINEERING IMrRov-EMENT COMPANY.. OF SAME iLAcnf.

i sMoKELEseF-bsriacs.

. .,'5 SPEOIFIGATXN forming part of'Letters latsnt` No.j542,294, dated July 9, 1895-'. f l

. ppnaion filed member i9, 1894. sei-1n nu 529,271. (No man.)

showing at the front of the furnace.

In the drawings, wall, which is offset at its upper frontcorner toreceive'a hollow casting B,- which may be cated bythe dotted lines in Fig. 3, Over the '.topof this casting a lining of Iirebrick' C is placed.. This casting provides' an` opening extending the width of the'bridge-wall less the partitions ofthe casting and opening'froni front to back.

erably made rectangular in cross-section .and hollow from end to end, and which `have fillets Wall and their open ends register at the rear seen-at d', Fig. .5, and the` oset portion' en- A represents thelbridges connection with dead'-plates made in sections of suitable length, asindi- D indicates the grate'bars, which are prff dcast on their sides in o1der" to'p1'ovide forl spacing them suitably apart. The grate-jbars have a support on a'ledge 'aot' the bridgewith the openings in the ca sting'B. lThe front en'dsof these grate-bars 'are offset, as

. gtssfover a secondary-bridge-wall, located inv du highly-heated serveas torches toignite the tersbetween two dead-plates E F, arranged trafnsverselyof the furnace near its front V75 plate G and spaced suflicient'distance apart to provide a passage H between them for the admission of air to-titey front'ends of the holt rear of, i the main. bridge-wall, and which 2 5 s pports aseriesofslabs or plates of fire-clay,- orxnther "refractory material, which being now inliammable mixture of smoke, gases, and ning. By this secondary combustion the smoke 3c is jaln;estf entirely consumed, intensifying the heatwithin1 the'furnacegand.avoiding the ",t'ffvgeinissiofr'of.the smoke into the atmosphere.

Tliefq'nantity of air admitted through the vh rillow'grate-bars is regulated` by valvesor -35 dempers which canbeloperated atthe front o'f tl1e furnac'e,-andthe-passage of the air th rough ,these hol-losv grate-bars not only serves to heat tb'eairfto; the proper' temperature, butv also sn'b,tra"ets-h'eat from the walls of the bars,- th-us Aprol'onging their usefulness.

In the accompanying drawings, Figure lis a 'longitudinal sect-ion ythrough` a steam-boiler furnace, .showing the boiler and connected' parts in elevation. Fig. 2 is an end elevation, 45.

partly in section,:through`a vpair of boilers, particularly intended to show the slabs or plates which serve as torches. Fig.'3 is a plan view ofthe grate-bars, bridgefwalls, and the plates mounted on one of said bridge-walls. Fig. 4 is an enlarged plan; and Fig. 5, an enlarged elevation of one of the grate-bars,

gratehandle K,nprojectedirough the front WallG ofthe furnace. lheratchet-teeth on this handle may be engaged with the plate G, through which the ratchet passes to lock the damper toanydesired'position. An opening plate G, as shown iu Fig. 2,the damper arranged outside the frontA plate to admit air to thespace H between the dead-plates 'The may be admitted in the usual way, xand this spacing-fillets.

In' the rear. of the bridge-wall A a secondthe gratebars,'which are provided by the lowgrate-bars. The-lower dead-plate may be edge'andiprovided with anoperating ratchetair tosupport combustion on the grate-bars.

or openings g, may be made through the front Y air willcirculate freely in the spaces between l 'IOO ary bridge-wall L is arranged transversely of the furnace, and this bridge-wall supports a series of slabs or plates M of some refractory material, such as iirc-clay. lThese slabs or plates are preferably set edgewise, as shown in Figs. 2 and 4, and spaced apart at suitable distances,so that the products of combustionand llame coming over the bridge-Wall Gand the hot air coming through the hollow castings B from the hollow grate-bars will meet and mingle in the vicinity of the plates 'or slabs M, the course of the currents being indicated bythe arrows in Fig. 1. This highlyheated air issuing beneath the llame, passing over the bridge-wall and mingling therewith,

will supply the necessary oxygen to support combustion of thesmoke and gases, which will be eiected by the highl'y-heatedplates M, whichthus serve as torches. This secondf ary combustion not only serves to sensibly increase the heat of the furnacefbut it further-serves to consume, to a large extent, the

` smoke produced bythe burning of the fuel in the primary combustion-chamber, thus making the furnace comparatively smokeless. The details of construction and the exact `proportions of the several passages may be varied'to some extent; but I preferably form air-inlet openings either in the lower dead- Y plate or in the front Wall of the furnace, as

may be preferred, and the area of these openings will be equal to the sum of the areas in `cross-section of the'series of grate-bars. By

, the manipulationof the damper the quantity sof air supplied may be regulated or controlled to suit the atmospheric and other conditions, and it is highly desirable'to get the proper progortions of oxygen from the air to combine wit thecarbon in the smoke to insure complete chemical combustion or combination.

When openings are provided in the lower t dead-plate and the air is admitted through y be in saiddoors; and in lieu of the platesA thel ash-pit door,l the dampers may of course some other'means--eg., a jet ot ame-may be used to effect the ignition of the smoke and gases; .l

y `I am aware that it has lbeen proposed to employ hollow grate-bars delivering' into a `chamber in the bridge-wall with openings from saidchamber at the back of the bridgewall. To this com mon provision I'add means for positively igniting the superheated air when mingled with the gases escaping over 'the bridge-wall, and this means I have herein designated as-a torch.

I claim-- l. In asmokeless furnace, the'combination with a bridge wall, of aseries of hollow gratebars communicating with the atmosphere and sides, a series of hollow grate bars communiv eating witih the front of said chamber at their rear ends and with the outer air at their front ends, a damper to regulate the admission of' air to said grate bars, and slabs or' plates arranged transversely of the furnace behind the bridge wall, substantially as and `forthe purpose described. v t,

3. In a smokeless furnace, the combination with bridgewall, a hollow casting mounted. thereon and having an opening at the front and rear of the bridge wall, linings applied to said casting, hollow grate bars communicatingr -at their rearends with said hollow casting and at their front ends' with the outer aina valve controlling the nir inlet and asecond bridge wall arranged in the rear of the first and slabs n or plates mounted transversely thereon, substantially' as described. l Y

v4. In a smokeless furnace,the combination with a bridge wall having van air chamber therein opening at the frontand rear of the bridge walhpf a seriesof hollow grate bars communicating with the atmosphere and opening at their rear ends into the chamber in the bridge wall, a torch arranged inthe rear of the bridge wall for .iguitng the co'mmingled gases escaping over the bridge wall, and a valve or damper arranged inthe airinlet and controllable from the furnace front, substantially as described.

5. A furnace grate, comprising in combina-l tion a bridge wall havingan air chamber in its upper portion opening at the front-[and rear ot the bridge wall, a series of hollow grate bars separated from each other longitudinally and communicating at` their rear ends with y said air chamber, dead plates arranged transversely to said grate bars and separated vertically to provide an air space between'them,=

a damper hinged in said space and a ratchet handle connected with said damper and projected through the front wall of the furnace, Asubstantially as described.

BENJAMIN ARTHUR THOMAS.A

Witnesses:

C. C. LINTHICUM, FREDERICK C. GOODWIN. 

